Originally Posted by
CKrueg
I read a few study's and for the most part pilot mass had the greatest effect. More mass resulted in a slower pressure spike and reduced injection delay. It actually increased smoke but reduced NOx and noise. It did have a positive effect if main timing was retarded but the overall efficiency was better with increased main timing and reduced pilot mass. As for timing it had a greater effect on noise when it was close to the main injection however the best results was with 2 smaller pilots spaced out. What I did was converted the timing from degrees to Ms and then spaced them out a certain time before the main injection. So basically one pilot is always starting around 1 Ms before the main and the other is one Ms before the other pilot. Also as load increases I spaced them closer to the main since in theory they should ignite sooner after injection meaning you need less advance
I'm not totally sure if this is best but the OEM map is all over the place which seems odd. My 6.4 ran great like this so I imagine it works well.